alex is correct. I take a coin from my pocket, flip it, and it lands on heads. I then do it again. For this second flip it is more likely to land on heads than tails.
Why it's 50:50
Simples
cos there's a chance the coin is biased, therefore you should account that chance into the probability for the next flip. The only information you have about the coin is that it has just been tossed on shown heads. Therefore there's a chance its biased towards heads so >50% for the next flip.
there've been studies done that show that a coin that is heads up at the start of a flip are more likely to come down heads, same for tails. however because the general method of flipping involves catching it and then turning it over onto the back of our hands then it's actually more likely to come down tails if the last flip was heads (unless we turn it over first then the opposite is true)
this study becomes irrelevant if we let the coin fall to the ground as it all goes to shit when it starts bouncing around
i agree totally with this too. it works and we had a guy in our pool team that always tossed the coin because he was pretty consistant at winning the toss for us.
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